Happy Bucket Challenge is a free online draw-the-line physics puzzle game where your goal is simple: draw paths that guide liquid into an empty bucket and make it smile. Each level gives you a blank canvas and a sad, dry bucket — you sketch lines freehand, and gravity plus fluid physics do the rest. Get the angle wrong and the water spills everywhere. Nail it perfectly and you score three stars.

What makes this game genuinely tricky is that there's no single correct answer. Some players route the water with one clean diagonal line; others build elaborate multi-step funnels. Both can work. Levels start straightforward but quickly introduce obstacles, awkward bucket placements, and tighter liquid volumes that punish sloppy line placement. Chasing that three-star rating on every stage is where the real replay value kicks in — your first solution gets the water in, but the optimal solution requires actual thought and creative geometry.

Happy Bucket Challenge works great for kids learning basic physics concepts and for adults who want a low-stress brain workout during a break. Fans of line drawing games, water flow puzzles, and casual physics games will feel right at home here. If you enjoy games like Cut the Rope, Where's My Water, or any glass-filling puzzle game, this one belongs in your rotation. Play it free in your browser — no download, no install, just draw lines and fill buckets.